The invention relates to a machine for making tea-filled double-chamber bags from a web of material which is continuously formed into a tube. Equally spaced tea portions are deposited in the tube, and a tube piece containing two tea portions is cut off. The cut-off tube piece is received by a transporting wheel. The transporting wheel have arms rotatably mounted thereon and arranged in pairs at equal angular distances for seizing the cut-off tube piece. Each pair of arms supports a W-shaped profile cooperating with a hold-down device for forming a bottom fold. Finally, another device forms a head fold.
German Patent Specification No. 1,001,944 discloses a machine of the type mentioned in which the bags are formed and closed solely by folding. In the process, the transporting wheel with a cut-off tube piece passes progressively through various work stations in which the bag bottom and, after the two parts of the tube piece are raised, the head are closed. Progressive execution of individual working steps inevitably produces a certain irregularity in the production sequence. There is a risk, because of a bag tea being a free-flowing packaged commodity, that the portions of tea will not remain accurately placed during the production operation. Even slight slipping or spreading of portions of tea can considerably impair folding of the bags if, as a result, tea is deposited in the areas of the tube pieces which are provided for the bottom fold and/or the head fold. Vibrations and shocks have a particularly adverse effect after the tube piece is cut off from the tube web until the parts of the tube piece which are folded in a W-shape are closed.
Because of ever increasing demand, an increase in the production capacity is necessary. German Patent Specification Nos. 2,120,270, and 2,405,761 disclose a machine for making double-chamber bags in which individual production units are mounted on a continuously rotating transporting means. In the known machines, although the bag web is held in place in the area of the future bag bottom even before the individual sections are cut off, the sections containing the portions of tea remain largely insecure until directly before the head fold is formed. Therefore, a risk exists, in particular during raising of bag sections by arms, of the tea being spread. This hampers subsequent formation of the head fold. In addition, the continuous operation of the transporting means, as a rule, is performed with higher rotational speeds and, consequently, higher centrifugal forces. Therefore, a continuous operation further increases the risk of spreading.